How to avoid hardware damage with dd

I wanted to create an encrypted USB-stick. In the tutorial I used it said something like 'to avoid pattern based attacks dump random input to the drive'. So I did by dding /dev/urandom to the drive. It took some time, the stick got really hot, but I tought whatever. I had to do that a bunch of times, becuase things did not work and now the stick does not answer any more. Does not show up on lsblk, does not show up on lsusb, does not light up when plugged in. Of course this can be a coincidence, but I would like to avoid that. So how can I? I have seen people pipe the dd input into pv, sth like this:

dd if=./sth.iso | pv | dd of=/dev/sdb

This is neat to see a progress bar. But I know you can use pv to slow down throughput through a pipe.

echo unix stackexchange|pv -qL 10

Now what is a safe amount of throughput? Are there other ways to avoid damage? Am I mistaken to think that I broke the drive with dd?